Civil war is raging through the Iraqi countryside. Sunni insurgents have largely taken control of the province of Diyala, where local leaders believe the insurgents are close to establishing a “Taliban republic”.

Officials in the strategically important province–composed of a mixture of Sunnis and Shias with a Kurdish minority–have no doubt about what is happening. Lt-Col Ahmed Ahmed Nuri Hassan, a weary-looking commander of the federal police, says: “Now there is an ethnic civil war and it is getting worse every day.”

At the moment, the Sunni seem to be winning.

As the violence has escalated over the past three years, it has become too dangerous for journalists to find out what is happening in the provinces outside the capital. The UN said last week that 5,106 civilians were killed in Baghdad in July and August and 1,493 in the provinces outside it.

Insurgents have cut the roads out of the capital to the west and the north. As I travelled through the provinces of this vast, war-torn country, despite keeping to the relatively calm tongue of Kurdish territory that extends through the countryside almost to Baghdad, I was keenly aware that it is not a place to make a mistake in map reading.

We drove for a couple of hours beside the Diyala river which rises in Iran’s Zagros mountains and looks like a smaller version of the Nile, a streak of vivid green vegetation running through dun-coloured semi-desert. Then we turned abruptly east before the road entered the strongly insurgent district of As-Sadiyah.

What could have happened if we had continued down the main road was evident at Lt-Col Hassan’s headquarters. In one corner of the courtyard was the wreckage of a blue-and-white police vehicle, ripped apart by a bomb. “Five policemen were killed in it when it was blown up at an intersection in As-Sadiyah two months ago,” a policeman told us. “Only their commander survived but both his legs were amputated.”

In Diyala, it is possible to see the anguished break-up of Iraq at ground level. Going by the accounts of police and government officials in the province, the death toll outside Baghdad may be far higher than previously reported. Ibrahim Hassan Bajalan, the head of Diyala’s provincial council–who had survived an attempt to assassinate him in Baquba with a mortar attack the previous day–says he believed that “on average, 100 people are being killed in Diyala every week.”

The latest were three civilians shot dead yesterday by unidentified assailants. Behind them, as the killers sped away in their car through the streets of Baquba, the families of the dead were left to grieve, falling to their knees and throwing their arms open to the sky in despair.

Many of those who die disappear for ever, thrown into the Diyala river or buried in date palm groves and fruit orchards. The reason for their killings can be spurious, and people have become careful to avoid incurring the wrath of local Sunni insurgents who control much of the province according to strict Islamic laws. “They have even banned the sale of cigarettes in the provincial capital, Baquba, and kill anybody selling cigarettes,” Mr Bajalan said. “I have to bring in cigarettes from other places to give them to council members who are smokers.”

In a house in Khanaqin, a Kurdish enclave in the north-east of the province, Nazar Ali Mirza, a sorrowful-looking middle-aged woman, described how she had fled too late from Muqdadiyah, the Sunni-dominated town of 200,000 people where she was born. She was caught by surprise when death squads began to target Kurds and Shias in her neighbourhood. Her eldest son, Khalil Mohammed Ahmed, a taxi driver, went out to collect a washing machine in March and never came back. She is beginning to assume he is dead but no body was discovered.

“Kurds and Shias were being driven out of our district,” she said. “Men in black masks came to me and said they would kill my sons, even if they flew up into the sky, unless I moved away.” One of her other sons was a policeman permanently disabled in a bomb explosion.

Mrs Mirza and her family are among 300,000 Iraqis forced to flee their homes since the beginning of the year. Everywhere, minorities frightened for their lives are on the move. “Nobody waits any longer to find out if a threat is real,” says Mamosta Mohsin, the leader of the Patriotic Union of Kurdistan in Khanaqin which, in effect, runs the town. “Even if the threat is organised by two children, people will run.” Most often, the threat is real. Lt-Col Hassan has a collection of files in which the names of the latest refugees are registered. Most of them are Kurds coming from Baghdad, Ramadi, Baquba and the rest of the country.

He hands over a piece of paper showing how the number of refugee families arriving in this small town had risen from 29 in January to 318 in June. It was still 239 in August.

Lt-Col Hassan says that neither Sunni nor Shia are particularly well organised: “It is not like Lebanon, because most of the killing is done by local or tribal militias.” The problem is not that the insurgents are strong but that the government forces are so weak. A division of 7,000 government soldiers is in Diyala, he said, “but they are all Shias and only arrest Sunnis.”

Mr Bajalan confirms that the army is weak in Diyala, saying most of it is tied down at checkpoints. He reckons there is one soldier for every 50 square kilometres of the province. “The soldiers are badly armed,” he says.

“They just have Kalashnikovs while the terrorists have rocket launchers and heavy machine guns. When they attack, they always kill 10 or 15 army or police.”

The Americans do have a base near Baquba, and act in a supportive role when they are asked to. “That isn’t much use against guerrillas,” says Mr Bajalan. “They’ve all gone home by the time the Americans arrive.”

Baghdad announced signal successes around Baquba last week, including the capture of leaders of two Sunni insurgent groups. But nobody in Diyala had heard about it, and, without exception, they expected the civil war to grow in intensity.